Canadian Application Publication

Title (French)

Chenilles pour vehicule tout terrain

Abstract (English)

The present invention is concerned with track assemblies for an all-terrain vehicle, which make it maneuverable and effective upon a variety of unstable, uneven, stable and even surfaces, while designed to maintain tension upon the endless track belts to keep them in their due course and prevent accidental loosening while having a punctually localized surface contact with a ground surface, and at the same time reducing the damages inflicted on the terrain.

CA 02372949 2002-02-251 TITLE OF THE INVENTION Track assembly for an all-terrain vehicle FIELD OF THE INVENTION[0001] The present invention relates to all-terrain vehicles. Morespecifically, the present invention is concerned with track assemblies for an all-terrain vehicle. BACKGROUND OF THE INVENTION

[0002] Traditionally, two types of all-terrain vehicles are proposedeither the wheel type or the tracked type.

[0003] Generally, a wheeled vehicle is more maneuverable than atracked vehicle, but is not as efficient on uneven or soft terrain such as, forexample snow.

[0004] Tracked all-terrain vehicles have been proposed, whichrequire complicated track assemblies comprising a track frame to maintain thetension of the endless track belt and prevent it from loosening. Furthermore,such vehicles have generally a large contact area with the ground, whichresults in a decreased maneuverability and an increased impact on the oftensoft terrain.

[0005] Therefore, there is still room for improvements toward an all-terrain vehicle provided with track assemblies, which is maneuverable andeffective upon a variety of unstable or uneven surfaces, while designed tomaintain tension upon the endless track belts to keep them in their due course

CA 02372949 2002-02-252and prevent accidental loosening, and at the same time reducing the damagesinflicted on the terrain. OBJECTS OF THE INVENTION

[0006] An object of the present invention is therefore to provideimproved track assemblies for an all-terrain vehicle. SUMMARY OF THE INVENTION

[0007] More specifically, in accordance with the present invention,there is provided an all-terrain vehicle comprising at least two track assembliesto support the all-terrain vehicle onto a ground surface, each one of said atleast two track assemblies comprising:a longitudinal endless track belt provided with an innersurface provided with a plurality of inner lugs and an outer surface providedwith a plurality of external lugs;a mounting structure to mount said longitudinal endless trackbelt to said vehicle,wherein, when mounted to said mounting structure, saidlongitudinal endless track belt has a punctually localized surface contact withthe ground surface.

[0008] In accordance with another aspect of the present invention,there is provided an endless track belt assembly comprising:a track driving wheel provided with a plurality of teeth;an endless track belt provided with an inner surface having aplurality of inner lugs and an outer surface having a plurality of external lugs,said endless track belt being wounded around said track driving wheel;

CA 02372949 2002-02-253wherein a) said teeth are so spaced that a distance betweentwo consecutive teeth spans a distance separating two consecutive inner lugsof said endless track belt and b) said endless track belt, when mounted to saidtrack riving wheel, has a punctually localized contact with a ground surface.

[0009] In accordance with another aspect of the present invention,there is provided a method for mounting an endless track belt on a all-terrainvehicle, comprising the acts of:providing an endless track belt having inner lugs and externallugs;providing a track driving wheel having a plurality of teeth sospaced that a distance between two consecutive of the plurality of teeth spansa distance separating two consecutive of a plurality of inner Lugs of the endlesstrack belt;interconnecting the track driving wheel to an inside idlerwheel and to an outside idler wheel; andtensioning the endless track belt around the track drivingwheel, the inside idler wheel and the outside idler wheel so that the endlesstrack belt has a punctually localized surtace contact with a ground surface.

[0010] Other objects, advantages and features of the presentinvention will become more apparent upon reading of the following non-restrictive description of preferred embodiments thereof, given by way ofexample only with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In the appended drawings:

CA 02372949 2002-02-254

[0012] Figure 1 is a side elevational view of an all-terrain vehicleprovided with track assemblies according to an embodiment of the presentinvention;

[0013] Figure 2 is a side elevational view of the front track assemblyof the vehicle of Figure 1; seen from of the outside of the all=terrain vehicle;

[0014] Figure 3 is a side elevational view of the front track assemblyof the vehicle of Figure 1, seen form the inside of the all-terrain vehicle;

[0015] Figure 4 is a sectional view taken along the line 4-4 of Figure3;

[0016] Figure 5 is an enlarged side view of an outside idler wheelattachment of the track assembly of Figure 2;

[0017] Figure 6 is a sectional view of a rigid member of the trackassembly of Figure 2;

[0018] Figure 7 is a top plan view of the attachment of the front trackassembly of Figure 1 to the all-terrain vehicle;

[0019] Figure 8 is a side elevational view of a rear track assembly of Figure 1, seen from the inside of the all-terrain vehicle; and

[0020] Figure 9 is a top plan view of the attachment of the rear trackassembly of Figure 1 to the all-terrain vehicle.

CA 02372949 2002-02-25 DESCRIPTION OF THE EMBODIMENT

[0021] A track assembly for an all-terrain vehicle according to anembodiment of the present invention will now be described in details withreference to the appended drawings.

[0022] Figure 1 shows an all-terrain vehicle 10 comprising a body 12and four track assemblies (only two shown) according to the present inventionarranged in a plane adjacent to each side of the vehicle 10.

[0023] There are two identical track assemblies in the front of the all-terrain vehicle 10, of which only one track assembly 14 is visible in Figure 1, inplace of conventional front wheels. Similarly, there are two identical trackassemblies, of which only one track assembly 16 is visible in Figure 1, in placeof the conventional rear wheels.

[0024] Only the track assemblies 14 and 16 visible in Figure 1 will bedescribed hereinbelow. Furthermore, as they are symmetrical about a verticalaxis 22 when viewed from the outside of the vehicle 10 (see Figure 1 ), only thetrack assemblies 14 will be described hereinbelow. It is also to be noted thatthe elements as seen from the outside of the vehicle 10 will bear the samenumbers in the rear track assembly 16 than the corresponding ones in the fronttrack assembly 14, with a prime.

[0025] However, since the attachment of rear and front trackassemblies differs as seen from the inside of the vehicles 10, they will bedescribed separately.

CA 02372949 2002-02-256

[0026] The front track assembly 14 is better seen in Figure 2. Itcomprises a longitudinal endless track belt 23 and a mounting structure tomount the endless track belt 23 to the vehicle 10. The mounting structureincludes a track driving wheel 24, a pair of inside idler wheels 26; a pair ofoutside idler wheels 28 and supports to interconnect the wheels 24, 26 and 28as will be described hereinbelow.

[0027] The endless track belt 23 is provided with inner lugs 30 on itsinner surface 31 and with external lugs 32 on its outer surface 33. It is woundedaround the track driving wheel 24 and the idler wheels 28 and 26.

[0028] As can be better seen from Figure 4, the track driving wheel24 is mounted to a conventional hub 35 of the all-terrain vehicle 10. The wheel24 includes a first mounting plate 37 mounted to the hub 35 and a secondmounting plate 34 mounted to the first plate 37 via four bolt and spacerassemblies 36. A circular disk 38 is mounted to the bolt and spacer assemblies36 and includes equidistant wide teeth 40 contacting the inner surface 31 of thetrack 23.

[0029] As will be apparent to one skilled in the art, the equidistantteeth 40 are so located as to cooperate with some of the inner lugs 30 of theendless track belt 23. More precisely, as can be better seen from Figure 2, theteeth 40 are spaced so that the distance between two consecutive teeth 40spans the distance separating consecutive inner lugs 30 of the endless trackbelt 23, in a meshing engagement, in such a way as to drive the endless trackbelt 23.

CA 02372949 2002-02-257

[0030] Each of the inside idler wheels 26 includes a peripheralportion in contact with the internal surface 31 of the track 23. The wheels 26are interconnected by a spacing element (not shown).

[0031] Similarly, each outer idler wheel 28 includes a peripheralportion in contact with the internal surface 31 of the track 23. The wheels 28are interconnected by a spacing element 42.

[0032] The wheels 24, 26 and 28 are interconnected, as seen fromthe outside of the track assembly 14, by an angled connecting element 44. Theangled connecting element 44 has a center portion 46 provided with anaperture 48 in which bearings 50 are mounted. A fastener 52 connects theconnecting element 44 to the second plate 34 while allowing the angledconnecting element 44 to pivot about the fastener.

[0033] The connecting element 44 has a short arm 54 having a freeend to which the inside idler wheels 26 are rotatably mounted. The connectingelement 44 also has a long arm 56 having a free end to which the inside idlerwheels 28 are rotatably mounted as will be further discussed hereinbelow. Theconnecting element 44 is better seen from the top plan view of Figure 6.

[0034] Turning now briefly to Figure 3 of the appended drawings, ascan be seen from the inside of the all-terrain vehicle 10, the idler wheels 26 and28 of the front track assembly 14 are also directly connected together by anelbowed connection element 58. The inside idler wheels 26 are rotatablymounted to a first end of the elbowed connection element 58 while the outsideidler wheels 28 are rotatably mounted to a second end of the elbowedconnection element 58.

CA 02372949 2002-02-258

[0035] The rotatable connection of the outside idler wheels 28 to theangle connection element 44 and to the elbowed connection element 58 willnow be described with reference to Figure 5.

[0036] As will easily be understood by one skilled in the art uponinspection of Figure 5, the tension of the endless track belt 23 is adjusted bythe connection of the outside idler wheels 28 to the elements 44 and 58. Forconcision purpose, only the connection of the wheels 28 to the elbowedconnection element 58 will be described.

[0037] With reference to the enlarged side view of Figure 5, atension adjusting assembly according to another aspect of the presentinvention will be described. As can be seen from this figure, a distal end of theconnection element 58 includes a slotted aperture 60 receiving a fastener 62used to rotatably mount the wheels 28 to the assembly. By sliding the fastener62 in the aperture 60, it is possible to increase or decrease the tension on thetrack 23. To adjust and maintain this track tension, a cam element 64, havingan outer periphery provided with notches 66 located at different distances fromthe attachment point of the element 64, is mounted to the fastener 62. Byselecting which notch 66 is in contact with a fixed pin 68 of the element 58, apredetermined tension may be maintained. It is to be noted that the camelement 64 is provided with a handle 70 to facilitate the manipulation by a user.

[0038] Returning to Figure 4 of the appended drawings the endlesstrack 23 will be described in greater detail.

[0039] As can be seen from Figure 4, the overall profile of the track23, from one side to the other, i.e. transversely, is generally convex. However,

CA 02372949 2002-02-259the convex profile of the track 23 is created by a lug arrangement comprisingtwo successive transverse rows of lugs arranged in a staggered relationship.

[0040] A first transverse row of lugs contains three lugs 72, 74 and76 and a second row of lugs contains four lugs 78, 80, 82 and 84. These lugsare symmetrical about a longitudinal axis (not shown).

[0041] A first lateral lug 72 of the first row includes three ground-contacting surfaces separated by two indentations. The shape of lateral lug 72is such that the ground contacting surfaces are generally transversally convex.

[0042] A central lug 74 is centered about longitudinal axis andincludes two ground-contacting surfaces separated by an indentation. Theground contacting surfaces are symmetrical about the longitudinal axis and aregenerally transversally convex.

[0043] A second lateral lug 76 is a mirror image of lug 72 about thelongitudinal axis.

[0044] The first and second lateral lugs 72 and 76 are laterallyspaced apart from the central lug 74.

[0045] In the second transverse row of lugs, a first intermediate lug80 includes two ground-contacting surfaces separated by an indentation. Theground engaging surfaces are slightly transversally convex.

[0046] A first external lug 78 includes two ground-contactingsurfaces that are separated by an indentation and are transversally convex.

CA 02372949 2002-02-25

[0047] Finally, the second intermediate lug 82 and the secondexternal lug 84 are respectively mirror images of lugs 80 and 78 with respect tothe longitudinal axis. For concision purposes, these lugs will not be furtherdescribed herein.

[0048] Of course, the sequences described hereinabove of the lugarrangement defined by the rows of lugs are repeated onto the entire externalsurface of the endless track 23.

[0049] As it is apparent from Figure 4 the ground contacting surfacesof symmetrical lugs 78 and 84 are not aligned with the outer surfaces of theother lugs to form a continuous profile. Indeed, the ground contacting surfacesof lugs 78 and 84 are more angled and exceed the convex profile defined bythe other lugs. This configuration of the outer lugs is advantageous since itfurther prevents the vehicle from tipping over during sharp turns at high speedwhen the vehicle 10 is severely tilted.

[0050] As will be apparent to one skilled in the art, the endless trackbelt 23 has a punctually localized contact surface with the ground: Indeed,since it is transversally convex, it generally touches the ground with a limitedsurface at any given time when the ground is hard. Furthermore, since thereare no guiding rails for the endless track 23, the external lugs only touch theground, when it is hard, in the vicinity of the wheel 24. These two combinedfeatures improve the maneuverability of the vehicle since it emulates thecontact of a conventional tire onto hard ground, given that a shortened length ofcontact of the endless track 23 with the ground surface reduces the resistanceto a turning force.

CA 02372949 2002-02-2511

[0051] Of course, one skilled in the art could designed anotherconvex profile of the external lugs of the track 23 andlor another arrangementof the mounting assembly of the track 23 to the vehicle 10 to obtain this « onepoint contact » feature without departing from the spirit and nature of the presentinvention. For example, one could provide a guiding rail having a convexprofile and transversally convex lugs to achieve similar results.

[0052] As mentioned hereinabove, the way the front track assembly14 is attached to the body 12 of the vehicle 10 differs from the way the reartrack assembly 16 is attached to the body 12 of the vehicle 10. These twoattachments will be described hereinbelow.

[0053] The front track assembly 14 is attached to the body 12 of thevehicle 10 in a fashion shown in Figures 4 and 7, while the rear track assembly16 is attached to the body 12 of the vehicle 10 in a fashion shown in Figure 8and 9.

[0054] As seen in Figures 4 and 7, the front track assembly 14 ismounted to a tubular wheel table 100 of the vehicle 10 by means of a generallytriangular plate 102 fastened thereto by a plurality of U-bolts 104, 106, 108 and110. A rod 112 is connected between the elbowed connection element 58 anda pivot 114 of the tubular wheel table 100. A first end of the rod 112 is attachedto the elbowed connection element 58 by means of rubber damping elements116, in such a way as to allow a vertical movement at this point of the rod 112in relation to the elbowed connection element 58. A second end of the rod 112is attached to the pivot 114 of the tubular wheel table 100 by means of an R-clip 120, in such a way as to allow at this point a horizontal movement of theplate 102 holding the tubular wheel table 100 relative to the elbowedconnection element 58.

CA 02372949 2002-02-2512

[0055] The front track assembly 14 is further attached to the body 12of the vehicle 10 through a conventional rod 150 of the suspension system ofthe vehicle 10 and a conventional rod 157 used for direction (see Figure 4).

[0056] As seen in Figures 8 and 9, the rear track assembly 16 ismounted to the body 12 of the vehicle 10 by a rod 212. The rod 212 isconnected on a first end to the elbowed connection element 58′ by means of arubber damping attachment 216. It is attached, on a second end, to a tubularchassis 130 of the body 12 of the vehicle 10 by means of a chipping joint 132fastened thereto by an R-clip 134.

[0057] From the above description of the fashion in which the frontand rear track assemblies 14 and 16 are mounted to the body 12 of the vehicle10, in relation to Figures 4 and 7, and 8 and 9 respectively, the presentinvention provides for track assemblies that are easily removed or mounted tothe vehicle 10, through using R-clips (120 and 134), which enabledisconnecting the track assemblies from the vehicle in a simple manner.

[0058] As stated hereinabove, the interior surface 31 of the endlesstrack belt 23 is provided with a plurality of equally spaced lugs 30, which ensurea positive engagement with the teeth 40 provided on the outer circumference ofthe wheel 24. In operation, the wheel 24 is coupled to a drive shaft, via the hub30, connected to an engine (not shown), in such a way that the engine drivesthe wheel 24 in rotation . The wheel 24 thus drives the endless track belt 23 bythe meshing engagement of the teeth 40 with the internal lugs 30 of theendless track belt 23.

[0059] It is further to be understood that the external lugs 32 on theexternal circumference surface of the endless track belt 23 respectively exert a

[0060] As people in the art will understand, the all-terrain vehicle ofthe present invention, provided with four endless track assemblies, can be usedfor a wide range of operations and terrain, while being highly mobile andoffering good running performance.

[0061] The endless track structure maintains an adequateconfiguration over a variety of surfaces.

[0062] It will be obvious to people skilled in the art that the presentinvention can be applied both in the case of a two-wheel drive vehicle whereinthe power is typically applied only to the rear track belt assemblies and the fronttrack assemblies merely facilitate steering, and in the case of a four-wheelvehicle, wherein power is independently provided to each one of the four trackassemblies.

[0063] As will be further understood by one skilled in the art, the all-terrain vehicle 10, equipped with track assemblies according to the presentinvention, may be viewed as a snow vehicle since it may be used on snow asefficiently as conventional snow vehicles such as snowmobiles, for example.However, the one-point contact feature of the present invention allows the useof the all-terrain vehicle on harder surface without the usual drawbacks oftracked vehicles.

[0064] Interestingly, the present track assembly system can equip allfour wheels of an all-terrain vehicle or only the front or rear wheels thereof,

CA 02372949 2002-02-2514since it only weakly reduces the speed of the vehicle relative to theunderground surface.

[0065] A further possibility would be to use track assembliesaccording to the present invention in place of the rear wheels of a vehicle, whilemounting skis in place of the front wheels thereof.

[0066] Although the present invention has been describedhereinabove by way of preferred embodiments thereof, it can be modified,without departing from the spirit and nature of the subject invention as definedin the appended claims.

(Source: IFI)

Track assembly for an all-terrain vehicle – CA 2372949 A1 – IP.com

1. An all-terrain vehicle comprising at least two track assembliesto support the all-terrain vehicle onto a ground surface, each one of said atleast two track assemblies comprising:a longitudinal endless track belt provided with an inner surfaceprovided with a plurality of inner lugs and an outer surface provided with aplurality of external lugs;a mounting structure to mount said longitudinal endless track beltto said vehicle,wherein, when mounted to said mounting structure, saidlongitudinal endless track belt has a punctually localized surface contact withthe ground surface.

3. An all-terrain vehicle according to claim 2, wherein saidplurality of external lugs form a lug arrangement comprising at least twosuccessive transverse rows of lugs arranged in a staggered relationship.

4. An all-terrain vehicle according to claim 3, wherein said lugarrangement comprises a first row of lugs and a second row of lugs, said firstrow of lugs being arranged in a first sequence comprising a first lateral lug, acentral lug and a second lateral lug; said second row of lugs being arranged ina second sequence comprising a first intermediate lug, a first external lug and asecond intermediate lug.

5. An all-terrain vehicle according to claim 1, wherein saidmounting structure includes a track driving wheel provided with equidistant

teeth contacting the inner surface of the endless track belt, said teeth being solocated as to cooperate in a meshing engagement with said inner lugs of theendless track belt.

6. An all-terrain vehicle according to claim 5, wherein saidmounting structure further includes an inside idler wheel and an outside idlerwheel in contact with said endless track belt, and at least one interconnectingarm between said track driving wheel and said idler wheels.

7. An all-terrain vehicle according to claim 5, wherein said trackdriving wheel includes a first mounting plate and a second mounting platemounted thereto by a bolt and spacer assembly supporting said teeth.

8. An all-terrain vehicle according to claim 6, wherein said trackdriving wheel is mounted to a hub of the all-terrain vehicle.

9. An all-terrain vehicle according to claim 6, wherein each one ofsaid inside idler wheel and said outside idler wheel includes a peripheralportion in contact with said internal surface of the endless track belt.

10. An all-terrain vehicle according to claim 6, wherein said atleast one interconnecting arm comprises an angled connecting elementprovided with a short arm having a free end to which said inside idler wheel isrotatably mounted and a long arm having a free end to which said outside idlerwheel is rotatably mounted.

11. An all-terrain vehicle according to claim 10, wherein said atleast one interconnecting arm further includes an elbowed connection elementinterconnecting said inside idler wheel and said outside idler wheel, wherebysaid inside idler wheel is rotatably mounted to a first end of said elbowedconnection element while said outside idler wheel is rotatably mounted to asecond end thereof.

12. An all-terrain vehicle according to claim 11, wherein saidendless track belt is under a tension that may be adjusted by a tensionadjusting assembly mounted to said at least one interconnecting arm.

13. An all-terrain vehicle according to claim 12, wherein saidtension adjusting assembly includes:a cam element rotatably and slidably mounted to a slottedaperture of said at least one interconnecting arm; anda pin fixedly mounted to said ar least one interconnecting arm tocontact the cam element;wherein one of said inside and outside idler wheels is so rotatablymounted to said cam elements as to be moved by a rotation of said camelement, thereby adjusting the tension of said endless track belt.

14. An endless track belt assembly comprising:a track driving wheel provided with a plurality of teeth;an endless track belt provided with an inner surface having aplurality of inner lugs and an outer surface having a plurality of external lugs,said endless track belt being wounded around said track driving wheel;wherein a) said teeth are so spaced that a distance between twoconsecutive teeth spans a distance separating two consecutive inner lugs ofsaid endless track belt and b) said endless track belt; when mounted to saidtrack riving wheel, has a punctually localized contact with a ground surface.

wherein the endless track belt is wounded around said inside idlerwheel and said outside idler wheel.

16. An endless track belt assembly according to claim 14,wherein said track driving wheel is mounted to a hub of an all-terrain vehicle.

17. An endless track belt assembly according to claim 15,wherein each one of said inside idler wheel and said outside idler wheelincludes a peripheral portion in contact with said internal surface of the endlesstrack belt.

18. An endless track belt assembly according to claim 15,wherein said at least one interconnecting arm comprises an angled connectingelement provided with a short arm having a free end to which said inside idlerwheel is rotatably mounted and a long arm having a free end to which saidoutside idler wheel is rotatably mounted.

19. An endless track belt assembly according to claim 18,wherein said inside idler wheel and said outside idler wheel are furtherconnected by an elbowed connection element, whereby said inside idler wheelis rotatably mounted to a first end of said elbowed connection element whilesaid outside idler wheel is rotatably mounted to a second end thereof.

20. An endless track belt assembly according to claim 15,wherein said endless track belt is under a tension that may be adjusted by atension adjusting assembly mounted to said at least one interconnecting arm.

21. An all-terrain vehicle according to claim 20, wherein saidtension adjusting assembly includes:a cam element rotatably and slidably mounted to a slottedaperture of said at least one interconnecting arm; and

a pin fixedly mounted to said ar least one interconnecting arm tocontact the cam element;wherein one of said inside and outside idler wheels is so rotatablymounted to said cam elements as to be moved by a rotation of said camelement, thereby adjusting the tension of said endless track belt.

22. A method for mounting an endless track belt on a all-terrainvehicle, comprising the acts of:providing an endless track belt having inner lugs and externallugs;providing a track driving wheel having a plurality of teeth sospaced that a distance between two consecutive of the plurality of teeth spansa distance separating two consecutive of a plurality of inner lugs of the endlesstrack belt;interconnecting the track driving wheel to an inside idler wheeland to an outside idler wheel; andtensioning the endless track belt around the track driving wheel,the inside idler wheel and the outside idler wheel so that the endless track belthas a punctually localized surface contact with a ground surface.